A wealth of data is available facilitating the creation of digital representations having a seeming 3-Dimensional (3D) solidity. For example, in the field of medical imaging, digital data is captured from imaging systems such as magnetic resonance imaging (MRI), computed tomography (CT), ultrasound, and the like, enabling a solid image representation to be rendered on a display device. During analysis of the data, a radiologist can, by means of a mouse, trackball, or other system, advance a plane through the digital representation, and at a desired point, a current plane or slice, can be reviewed. Hence, a radiologist, surgeon, or other medical personnel can review images slices and compare the images with expected or anticipated results, unexpected results, etc., to facilitate detection of injury, e.g., broken limb, or an abnormality such as cancerous growth.
Typically a slice is moved through a 3D image (e.g. created from a data set) by employing an orthogonal coordinate system, where any point in a plane is uniquely represented by three orthogonal coordinates signing distances in relation to three mutually perpendicular axes, e.g., x, y, and z. In a conventional system, a plane is orientated in a 3D representation by selecting the position of the plane in any of three orthogonal 2D representations, e.g., a first representation along the x axis, a second representation along the y axis, and a third representation along the z axis. Moving a plane in any of the three orthogonal representations results in a corresponding motion of the plane in the 3D representation. However, owing to employing any of the orthogonal 2D representations to facilitate selection and movement of a plane, for any given operation of selection/movement, the orientation of the plane is only effected in two dimensions in the 3D representation. Hence, orientation of a plane, particularly an oblique plane, can be awkward and time consuming.